This invention relates to a control system of civil work vehicles for automatically running such civil work vehicles as dump trucks along a predetermined running course.
As means for conveying mined ores from an ore loading station, there to a crushing station are generally used large dump trucks having a loading capacity of from 30 to 50 tons. It has been the practice to travel between the loading station and the crushing station by manually driving the dump trucks by drivers.
However, where the field of view is narrow in night time or in mist or fog, or where there is plenty of dust or noise the drivers are obliged to work under a very difficult condition.
The manipulation of a dump truck relies upon manual operation of a hoist lever by the operator. Accordingly, if the operator manipulates the hoist lever roughly, there will occur such troubles as rupture of a seal on a hoist cylinder and damage to the dump truck due to an undue load. Actually, the hoist lever is too often manipulated extremely roughly.
Where a plurality of civil work vehicles are operated between a loading station and an unloading or crushing station, it is necessary for the drivers to keep a sufficient distance between a preceding vehicle and a succeeding vehicle for preventing collision. This requires not only a troublesome manipulation but also showing down of the running speed, thereby decreasing working efficiency.
To prevent collision there has been used a control system permitting only one vehicle to run in a predetermined running block. One such system is the ATS (automatic train stop) or ATC (automatic train control) system utilized to control railway trains. In such a system, however, it is necessary to install means for detecting the vehicle at the entrance and exit of each block. The cost of installation of such a system is extremely expensive.